Edge-grinding machine



Dec. 14 1926.

w. E; WHITE EDGE GRINDING M ACHINE Filed May 19, 1925 INVENTOR. WALTER E. WHITE.

ATTORNEY.

Patented Dec. 14, 1926.

UNITED sraiss PATENT OFFICE.

WALTER E. WHITE, or nAsnUA, new nAMrsHInE.

EDGE-GRINDING MACHINE.

Application. filed May 19, 1925. Serial No. 31,426.

10 tomary to manually or mechanically effect a relative traversing movement of the wheel or the article being acted upon by the wheel, to avoid wearing a groove or grooves in the periphery of the wheel. And of course it is desirable that such traversing movement shall be just sufficient to cause equal wear the full width of the periphery of the wheel. If the article or articles successively operated upon are always of thesame thickness laterally, the amount of traversing movement can always be the same. But if. for instance, only a single lens is to be ground at one time and at another time two or more lenses clamped side by side are to be ground,

25 there must be a change in the amount of the traversing movement if the wear of the periphery of the wheel is to be uniform across its full width.

The principal object of this invention is to provide a grinding machine in which the relative lateral movement of the grinder and the article or articles being operated upon will be automatically reversed when one side or the other of the article or articles reaches one side or the other of the periphery of the grinder, and having means whereby the amount of the traverse may be varied ac cording to the thickness of the article or group of articles relatively to the width of the periphery of the grinder, whereby the wear of the grinder will be uniform from one edge to the other of its periphery,-

whether the lens or. other article or articles be thick or thin.

With the above and other objects as hereinafter referred to in. view, the invention consists in the construction and combination of parts substantially as hereinafter de scribed and claimed.

. Of the accompanying drawings which illustrate one embodiment of my invention in which a lateral or traversing movement is imparted to a grinding wheel rather than to an article which is to be ground Figure 1. is a plan view of the machine.

Figure 2 is a side elevation of the same. Figure 3 1s a detail view, on a larger scale,

partly in section, looking in the direction of the arrows 3 in Figures 1 and 2.

Figure 4 is a detail elevation of someof the elements of the machine which are partly shown by Figure 2. I

Similar reference characters indicate similar parts in all of the views.

A suitable water-containing base 12, having a partial cover plate 11, is provided with bearings 13 for the shaft 14 of the grinding wheel 15, said shaft being both rotatably and slidably mounted in said bearings. The

shaft and its wheel are rotated at high speed by any suitable motor through a belt engaging a pulley 16 secured to one end of the shaft. The other end of the shaft carries a worm 17 meshing with a worm wheel 18 secured to a shaft 19 mounted in bearings 20 supported by a bracket 21.

The shaft 19 has a worm 22 meshing with a gear or worm wheel 23 which is secured to stud shaft 24 mounted in a bearing 25 pro jecting from the bracket 21. Mounted on the stud shaft 24, as with a splined connection, so as to berotated by the shaft but longitudinally adjustable thereof fora purpose explained hereinafter, is an arm 26.'

A wheel 27. hereinafter referred to as a cam, is pivotally connected at 28 to one end of the arm 26, and diametrically opposite said pivot the cam carries a screw 29 the inner end of which bears against the other end of the arm 26. By turning the screw 29 the cam can be tilted more or less relatively to a plane perpendicular to the axis of the shaft 24.

The outer face of the cam bears against a roll 30 carried by a lug 31 of an arm 32 pivoted to the base at 33 and having a yoke 34 engaging a grooved collar 35 secured to the outer end of the grinding wheel shaft 14. A spring 36 connecting the arm lug 31 with a suitable fixed point efiects return move- 1 distance determined by the angle to which the earn 2'? has been adjusted by the screw 29a I will now describe the work support as it is constructed for properly holding and rotating lenses the edges of which are to be ground :A work-supporting bracket 87 is formed at its lower edge with lugs 38 which receive the inner ends of bearing screws 39 mounted in small lugs or uprights 40 of the plate 11. The upper edge of said bracket is divided to form bearings 41, 42, 43, in alinement. Mounted in said bearings are shafts 44, 45, carrying at their inner or adjacentends pads or disks 46, 47, to grip the work between them. Details of these shafts will "be explained hereinafter.

The desirable slow drive of the shafts 44. 45, is obtained from the shaft 19. To this end the shaft 19 has a bevel pinion 48 meshing with a bevel gear 49 carried by a stud shaft mounted in the adjacent lug 40 and carrying also a pinion 50 which meshes with a pinion 51 carried by one end of a long shaft 52 which extends through to the other side of the pivoted bracket 37. Said pinion 51 transmits motion through a small pinion 53 to the gear 54 of the shaft 44.

The long shaft- 52 at its other end has a pinion which transmits motion through a small pinion 56 to the gear 57 of the shaft 45.

The shaft 44 is of suitable construction, as of two parts screwed together, so as to carry a pattern disk 58 of any desired shape, the construction of said shaft being such that pattern disks of different shapes may be substituted one for another. Said shaft requires no longitudinal adjustment. That is. its end disk or work-engaging pad 46 preferably remains always in about the position indicated in Figure 1. The other work-en gaging disk 47 however is adjustable by means of its shaft, to enable articles of differcnt thicknesses to be clamped or gripped between the two revolving disks, or to enable either one or a plurality of articles, duplicates as to form, to be so clamped or gripped. To this end the shaft 45 is "ariable in length, as by making it of a plurality of sections screwed together, one of said sections having a milled disk 59 in the space between the bearings 42, 43, to enable that section to be rotated in order that the shaft as a whole may be increased in length to force its disk 47 toward the disk 46 to clamp the work, or decreased in length to withdraw the disk 47 tov release the work.

If the article to be ground is a thin one, the traverse-controlling cam 27 is adjusted to occupy a practically extreme tilted position so that the grinder will be shifted back and forth laterally to an extent substantially equalling the width of itsperiphery to cause equal wear from side to side. ut if the article is a thick one, or if aplurality of articles are clamped side by side between the disks 46, 47, then the cam is adjusted to cause less lateral shifting of the grinder, so

that neither side of the article or group of articles will ever he in a position out of contact with the grinder.

I will now describe the mechan sm for causing the edges of the lenses or other ar ticles to bear properly against the grinder to shape the articles, by controlling the swinging moven'ients of the work-carrying bracket 37.

An angular-shaped arm 60, pivoted at 61 to lugs rising from the plate 11, has an upright linger bearing against the pattern disk 58, and is formed witn a horizontal threaded extension 63. Fitting the extension 63 a cone-shaped nut 64 having a knob 65. Mounted in a rigid bridge-piece (56 above the cone nut 64 is an adjustable set screw 6? the lower end of w iich forms a stop coacting with the inclined upper surface of the cone nut in determining the position of the finger (52 relatively to the axis of rotation of the pattern disk 58.

As indicated in Figures 1 and 2, the shank of the cone nut is provided with scale marks. A pointer 68 projecting from the bridge piece 66 coacts with said scale marks to in dicate various adjustments in the distance of the control linger 62 from the axis of rotation of the pattern disk 58.

When one or more lenses or other articles are gripped or clamped between the rotary disks 46, 47, as indicated by the broken lines in Figure 1, and the machine is in operation, said articles are revolved slowly and their edges bear a ainst the wheel 15 with such pressure as 1S due to the swinging bracket 37 gravitating to and the said wheel 15. Since the control linger 62 remains stationary in the position to which it has been adjusted by the cone-nut 64 cooperating with the stop-screw 67, the limit of inward swinging movement of the work-carrying bracket 37 is determined by the pattern disk riding against. said linger 62. Qbviously therefore, if an oval or other shaped disk is substituted for the circular one illustrated. the bracket 3'? will swing toward and from the wheel 15 so that the articles will be ground to a shape corresponding with that of the pattern disk. Accuracy in this re- ;pect is ensured, due to the pivot 1 of the arm 60 being in alinement with the pivots 23.) of the bracket 37, as indicated by coinparing Figures 1 and 2. The pattern disk will always contact with the same portion of the face of the finger 62 regardless of wear, thereby ensuring accuracy of the work done.

It is sometimes desirable to true the wheel 15 by moving it laterally in less time than would be required by the speed-reducing worm gearing between the shaft 14 and the cam-carrying stud shaft 24. To provide for this, the arm 26, (see Figure 3) is splined on the stud shaft 24 and is adjustable thereon as by means of a screw 69 passing llll 1,e10,ess

through the arm 26 and bearing againstthe outer face of the wheel 23. Said screw '69 can be quite rapidly operated manually to cause the cam to shift outwardly or back so as to cause the arm 32 to reciprocate the wheel shaft 14 while a tool is being held against the periphery of the wheel 15 to true it.

full width of the periphery of the wheel 15 but to pass beyond the side edges thereof so as to leave no edge ridges.

I do not limit myself to the operation upon articles which are to be rotated dur ing the grinding thereof. For instance, by interrupting the train of gearing, as by removing the gear 429 or shifting it out of mesh with the pinion 48, the shafts 4A, 45, will not be rotated. Then any article can be clamped between the disks 16, 47, and will be ground or sharpened by the wheel 15, the latter still having the same lateral traversing movement as hereinbefore described.

In operation, the shaft 14, carrying the grinding wheel 15, is driven at high speed and its worm 17 causes thecam 27 to rotate slowly, through the medium of the worm wheel 18, shaft 19, worm 22, and the worm wheel 23 which is secured to the stud shaft 2 1, the latter carrying said cam. The cam, acting on the roll 30 of the lug 31 of the lever arm 32, imparts a slow traversing movement to the grinding wheel shaft. The fact that the Worm 17 moves longitudinally with the shaft 14 does not interfere with effective operation of the machine since the only effect of such movement is that when it is moving in one direction the worm wheel. 18 is rotated a little faster than would be the case if the worm 17 did not move endwise, and when moving in the return direc tion the worm wheel 18 is rotated a little faster.

By reference to Figure 2 it will be seen that the lug 31 projects from the arm 82 at a point nearly mid-way of the pivot or fulcrum of said arm and its upper end which has the yoke 34:. Therefore the cam need not be very large, nor tilted very far, because the extent of traverse imparted to the grinding wheel is substantially double the amount of motion imparted to the lug 81 by the cam.

And such screw 69 can be actuated to cause the truing tool to operate not only the Having now described my invention, I claim I 1. A machine of the character described, comprising a grinding wheel and a work holder one of which is laterally movable relatively to the other, and means for variably controlling the amount of said lateral movement, said means including a rotary arm, a circular member pivotally connected to said arm at one side of the center of said member the free end of said member being laterally adjustable relatively thereto, and a lateral-movement-controlling member contacting with one face of said circular memher.

2. A grinding machine having an abrading wheel, a workholder, and means including a circular adjustable cam pivotally supported at its periphery for effecting a traversing movement of one relatively to the other.

3. A grinding machine having a slidably mounted power-driven shaft carrying an abrading wheel, a rotary work holder, worm gearing for transmitting motion from said shaft to the work holder, an arm connected to rotate with one of the members of the worm gearing, a cam wheel pivotally connected to said arm at one side of its center, means for holding said cam wheel more or less tilted, and means operated by the outer face of the cam wheel for effecting longitudinal movement of the abrading wheel shaft. 7

4:. A machine of thecharacter described, comprising a grinding wheel, a rotary work holder pivotally mounted to permit the work to gravitate toward the grinding wheel and carrying a pattern disk, a pivoted arm having a finger against which the pattern disk bears, the pivots of said arm and work holder being in axial alinement, and means for adjustin said pivoted arm.

5. A grinding machine having an abrading wheel, a work holder, and means in cluding a circular adjustable cam pivotally supported at its periphery forefi'ecting a traversing movement of one relatively to the other, means being provided for bodily shifting'the cam to impart quick traversing movement when desired.

In testimony whereof I have aflixed my signature.

WALTER E. VHITE. 

